In a recent discussion for People's "The Jess Cagle Interview," Jake Gyllenhaal opens up about how he dealt with Heath Ledger's death in 2008.
The two actors, who starred together in Ang Lee's "Brokeback Mountain," became close during filming and developed a friendship, making Ledger's untimely death even more difficult.
At the time, the "Donnie Darko" star was just 27 and, understandably, hadn't given death much thought.
"Personally, it affected me in ways I can't necessarily put in words or even would want to talk about publicly," he told Jess Cagle. "In terms of professionally, I think I was at an age where mortality was not always clear to me."
"I think you live in this bubble, too, of making films ... There are real friends, and there is a real community. There is also that [new Macklemore song] where he says, 'The curtain closes and nobody notices' ... I think that's true, and I think that's OK," Gyllenhaal said. "But I think at the time, I assumed everyone would notice -- and they did with Heath dying, but I think it [gave me] the experience of, 'This is fleeting.'"
The actor, now 35, went on to say that he realized, after Ledger's death, that the success of a movie isn't the most important thing to focus on.
"What matters is the relationships you make when you make a film, and the people you learn from when you're preparing for a film," he said. "That changed a lot for me."
Watch the full interview above.